Rapid centric vertical finder



Aug. 28, 1956 c. R. O'DONNELL 2,750,267

RAPID CENTRIC VERTICAL FINDER Filed June 20, 1952 INVEN TOR.

United States Patent 2,760,267 7 RAPID CENTRIC VERTICAL FINDER Charles R. o Donnell, Cleveland, Ohio ApplicationiJuneih, v1952, Serial N0. 294,693

' 3 'CIai1'i1s. on. 32-19 This invention .has relation. to the centric; and vertical and protrusive bite positioning of upper and lower jaw models on adental articulator;;reproducing: on the latter these positions as they existin the mouth.

It is the'object ofthisinvention to-reproduce these positions withoutthe necessity of the conventional. wax bite. rims., This eliminates the drawntout carvings requisitetto building free gliding waxsurfacesv so-bite rims may. move laterally and occlusally in. order that the scribing; units; (scribing screw and table) imbedded. in them can function in unimpeded, jaw excursions.

A further object of this invention-is that its lower member in combination with its. upper provides the dentist direct vision when, its scribing pin isregistering centric positon on. its scribing table. It; structure: elimi: nates the use of an, extraoral Gothicarch scriber now necessary for definite verification of; this position, viz., that the scribing pinqison thetapex. of the scribed Gothic arch. As is known all present devices for scribing the Gothic arch require their mountingin waxbite rims, and when pin is on. apex bite rims must be inocclusion; thus blocking ofi vision. ofv centric position, Ihisneces: sitates a device outside the-mouth--.an-extraoral Gothic arch tracer -to verify. definite centric position.

Another object. of my invention istoprovide a lower member, secured to the lower base plate; having;anup; right, such as a. screw.- associated, therewith, which may be adjustedtto appsition in which it.will clicle against a member secured, to' the-uppen base plate when. the basetplates are positioned in the patientsjaws and. the patients lipsf are closed to a position in which. he pronounces the letter M;

A further specific objectof thisinventionis its guiding facility in providing a precise protrusive excursion in the median line for the protrusivebite. This 'difl ers from the protrusive bite of the prior art, taken with a heated mass of. wax interposed between thefbite-rims and devoid of any guiding device, as will behereinafter detailed;

A further object ofthis invention is that its structure provides the innovation of a detachable scribing table permitting the quick locking on of the table to its lower member with a single screw. This operation diflfers from that of the prior art in that it saves the time now necessary in fitting a scribing table into a wax bite rim.

Fig. 1 is a front elevational view of my improved structure, the base plates being shown in the patients jaws and an adjustable upright being arranged between a member secured to the lower base plate and a member secured to the upper base plate with the upright being in the position it occupies when the patents lips are closed to pronounce the letter M;

Fig. 2 is a side elevational view of the structure shown in Fig. 1;

Fig. 3 is a bottom plan View of the upper base plate and the member secured thereto taken on a plane passing through the dash-dot line of Fig. 2, looking in the direction of the arrows 3; and

Fig. 4 is a top plan view of the lower base plate and 1 2,760,267 Patented Aug. 28, 1955 2 6 ers secured thereto taken on a plane passing through the dash-dot, line of Fig. 2, looking in the direction ofthe arrows4.

Referring. toithe drawing, the numeral 7 is a horseshoe-shaped member which is secured to the base plate 14 which base-plate is adapted-to be seated in the lower jaw of a patient as shown, in Figs. 1 and 2. The scribing table 8.. is vsecured to. the horseshoe-shaped member 7 by suitable means, such as ascrew. or bolt 1. Associated with the, member 7,is an upright, such as a screw 6 having a knurled: upper portion which screw is ad.- justably mounted in the horseshoe-shaped member 7 to such position. that it will-v contact the uppermember the instant the patients. lipsmeet: in pronouncing the letter M which establishes thevertical dimension as shown at 5-, inFig. 1. 2. shows scribing screw with a vertical rangeof space to roof vault 3. 16' is upper base plate seated in upper jaw.

Fig. 2 is a side. elevation of Fig. 1 showing knurled screw contacting. upper member at vertical dimension as shown by M contact of lips 421ml 4. Scribing screw 2 contacts its table andwill maintain this correct vertical. dimension. at which: the Gothic arch must be scribed-after. knurled screw 6 is removed for the scrib- 111g.-

In Fig. 3, 11;is .upper. member a crosspiece of metal or plastic attached directly to its base plate 10. If of plastic its expanded anterior willv beof a metal surface to produce, a metallic sound when knurled screw of lower member makes contact with upper in. pronounciation. This upper memberisthreaded-at its center to carry vertical scribing screw. 2. His amedian guide notch. The anterior. of. thistlnernber is expanded to permit marking by knurled screw. of the requisite 6.millin1eter protrusive bite shown as. line 13. Anterior and posterior dots on 13 are guiding pointsin line with median notchexplained later in operation. ofthe device.

.lnFigs. 2 and;4 14.is the lower base plate. Sealed to it is horseshoe shaped;v lower member 7 with its anterior knurled screw- 6. Locked to; it by screw on right is scribing table; 8.. 2:is.- centric position at apex of Gothic arch tracing. scribing table 8 is provided with a perforation or:ap erture .to receive the; knurled screw 6 associated with the horseshoe-shaped lower member 7.

, Operation of'the device-In phase 1 of centre-vertical registrati n,v the securing of jaw separation or the verticaldimension, the prior art uses the prosthetic concept thatthisseparation is the one thatexists the instant the waxbite rimscontact whenthe patient says the letter M: Thus. is required the construction of wax bite rims with. the occlusal carving down or building of the latter to thisdimension. The factor: ofvision makesthis operation tentative rather than exact for at the instant of occlusal contact in pronouncing the guiding syllable M the lips must be closed. This inadequate vision forces the dentist to rely on his judgment in reference to the occlusal contact. To avoid this common visual handicap this invention uses sound instead of vision for this operation. While patient says letter M knurled screw is turned up until it clicks against upper member signalling a precise vertical registration as shown by 5 in Fig. 1. It-

will be understood that scribing table 8 in this figure would be absent to permit pronouncing M. After this vertical registration is completed the knurled screw is turned down 3 millimeters to provide the conventional three millimeters free way space so plates will not click when talking. Without this conventional 3 millimeter space teeth would chatter, for in talking or in relaxation our lower jaw hangs down 3 millimeters.

Phase 2.Referring to the prior art as it now secures the Gothic arch tracing to locate centric position, the occlusal wax surfaces spoken of in vertical dimension unguided operation.

in turn have to be carved into their lateral relations to permit the unimpeded lateral arc swing of the lower jaw. Free lateral gliding wax bite rim surfaces would be essential before the scribing members built into them could correctly trace the Gothic arch/"This extended labor this invention eliminates sineeits structure provides a rapid nonimpeded and visible scribing of the Gothic arch. While knurled screw 6 in Fig. 2 maintains the vertical dimension, scribing screw 2 is moved down to table contact maintaining this dimension. Knurled screw is then removed to permit ;a visible nonimpeded Gothic arch scribing. Then-patient bites on apex of, centric position, as upper and lower members are sealed together with plaster for transfer to dental articulator, reproducing on the latter centric -,and vertical relations as they exist in the mouth. 1 L g I,

Phase 3 of centre-vertical relations; the protrusz've bite.In prosthesis this is expressed as that progressively greater jaw opening that occurs .posteriorly when lower teeth are protruded in'a median line 6 millimeters forward into an incisal bite.

In the prior art this is secured by interposingaheated mass of wax between bite rims'and having the patient bite forward 6 millimeters in a median liner-The bite rims are then seated on their modelswhichhave already been placed in centric and vertical position on the articulator down into table contact. the lengthened screw would exactly register this posterior bite opening for the articuand they are closed into this protrusive bite wax imprint.

This seating of the 'models into 'im rintsWingS-the condylor pitch indicators of the articulator into whatever jaw opening the wax mass imprint ofiers. With patients who are awkward in jaw movement it is often difiicult to get-the patient to. bite a-median 6 millimeter protrusive excursion into a wax mass since this is an The structure of this invention provides a guided median and anterior 6-rnillimeter protrusive excursion to register the purpose of this excursiontheposterior jaw opening. Both members are placed on the articulator lator. Placing the member on the articulator and closing it as was done on the 'wax bite imprint its condylor indicators would swing to the pitch or posterior jaw opening registered by the lengthened scribing screw thus providing the precise requisite of the protrusive bite.

Having. described the new is:

1. The combination ofupper ,andolowerqbase plates, an upper member secured to the upperbase plate, a horseshoe-shaped member securedto the lower base plate, a screw mounted in the horseshoe-shaped member, a scriber table arranged overthe horseshoe-shaped member and having an aperture through vwhich said screw extends, means for securing the scriber'table to the horseshoe-shaped member, and said. screw being adjustable to a position-in which-it engages theupper member when the plates are in the jaws 'Of 'apatients mouth and the patients lips-are closed to aposition in which he pronounces the letterM.

2. The combination of upperan'd lower base plates, an upper member secured to the upper base plate, a horseshoe-shaped member securedfito thelower base plate, a screw mounted in the liorseshoe-shape'dmemher, a 'scriber. table arranged over the horseshoe sha'ped plate and having an aperture 'throug h which said screw extends, said screw beingfadjustable to a position in and it is closed in'centric position permitting a centric This operation is more easily visualized in side'elevation I Fig. 2. It may be seen that if the patient; bites the knurled screw out 6 millimeters against'upper member the table 8 would move away from the scribingscrew point registering the progressivelygreater posterior jaw opening space. If while the patient bit onthe 6 millimeter median anterior protrusive guide .bit'e'marked on upper member and the dentist turned the scribing screw which it engoges the upper member when the plates are in the jaws of a patient and the patients lips are closed to a position in which he pronounces the letter 'M, and a scribing screw mounted in the"'upper"niemberand being adjustablefto a position in 'which it engages the scriber table when the lower 'jaw ofj the patient is moved outwardly to a; protrusi've-bite position.

3. The combination of upperandf lower base plates,

an upper member "secured to the'fupper base plate, a lower membersecu'red to the lower' base plate, a screw mounted in the lower member, a s'cribertable arranged over the lower membe'rand having an'aperture through which said "screw extends',sa-idi screw being adjustable to'a position in which it'eng'ages the upper member when the plates are in the jaws of a patient and the patienfls lips are closedi'to. a' position in whichhe'pronounce's the" letter M," and a scribing screw mounted in the upper,

member and. beingadjustableto a posit-ion'inwhich it engages the 'scriber table when} the lowerfljaw of the patient is moved outwardly to a protrusive' bite-position.

Leathers invention what is claimed as July 24, 1951 

